The invention relates to a multipurpose kitchen machine with a working container for receiving the food to be processed and an interchangeable rotating tool, driven by an electric motor and projecting into the working container.
A plurality of such kitchen machines are known which have in common the fact that the electric motor drive and the working container are releasably connected to form one unit during use, from which unit the working container can be disconnected for emptying, refilling, and cleaning by a few motions of the hand. The machines can optionally be equipped with various tools for performing the various jobs which can be done with them, such as mixing, cutting, stirring, beating, or kneading. The driving motion is transmitted from the electric motor to the interchangeable tool in question either from above by means of drive elements housed in a removable or foldable arm which projects over the upper edge of the working container in the direction of its interior, or from below by means of a drive shaft which is guided upward through a vertical dome formed concentrically with respect to the central axis of the working container.
In accordance with the universal nature of these multipurpose kitchen machines, they are generally equipped with a single working container, which is movably mounted or firmly locked to the base or housing of the machine and which receives the food for all the processing steps which can be carried out with the multipurpose kitchen machine in question. Formerly, limitation to this single working container meant that it had to be emptied and cleaned each time after processing a batch of food, before another batch with a different taste could be processed. This proved to be especially burdensome because of the effort and time involved when these various batches were components of a given recipe and had to be combined after their separate processing to form a complete dish. Mention is made only by way of example in this connection of recipes in which initially both stiffly beaten egg whites or whipped cream and a mixture of various ingredients, for a cake batter, is to be prepared, and then the two components, i.e. for example the egg white and the batter mixture, have to be combined with each other.
Another disadvantage of conventional working containers which has been accepted heretofore in the interests of the universality of multipurpose kitchen machines is that they contained a suitable working container which, although it was sufficient for the majority of interchangeable tools used and the extremely different types of foods to be processed, could only be a compromise as far as specific requirements were concerned, e.g. preparing egg whites or processing extremely small batches. The possibility of equipping every kitchen machine with at least one additional special working container has heretofore been a possible solution to the problem only in exceptional cases if only for cost reasons, since the manufacturing costs of the known working containers have imposed a considerable additional burden on the purchaser because of the high quality requirements imposed on them as regards safety and lifetime. In addition, storing additional working containers of the conventional type generally poses problems due to space limitations in the kitchen.